US3236708A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Etching of metals
Assignee: FMC Corp
•
Filing: 1963-04-24
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Granted: 1966-02-22
•
Expires: 1983-04-24
Abstract
No abstract record available.
Inventors
- 👤 William J Tillis
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 20:26
CPC Classifications
H; H05; H05K; H05K3/00; H05K3/02; H05K3/06; H05K3/061; H05K3/062; C; C23; C23F; C23F1/00; C23F1/02; H05K2201/00; H05K2201/03; H05K2201/0302; H05K2201/0305; H05K2201/0332; H05K2201/0335; H05K2201/0338
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
137 words
METHOD OF ETCHING COPPER BEARING A NOBLE METAL RESIST WITH AN AQUEOUS PEROXYDISULFATE SOLUTION WITHOUT PROVIDING EXCESSIVE UNDERCUTTING OF THE COPPER RELIEF PRODUCED THEREBY, COMPRISING PROVIDING A NOBEL METAL RESIST PATTERN ON THE SURFACE OF A METALLIC COPPER OBJECT, PROVIDING ON SAID RESIST PATTERN A COATING FROM THE GROUP CONSISTING OF TIN COATINGS AND COATINGS COMPOSED OF A TIN ALLOY FROM THE GROUP CONSISTING OF TIN-LEAD AND TIN-NICKEL ALLOYS CONTAINING AT LEAST 25% OF TIN, CONTACTING THE RESULTING WORKPIECE WITH AN AQUEOUS SOLUTION CONTAINING FROM 5% TO ITS SOLUBILITY LIMIT OF A PEROXYDISULFATE FROM THE GROUP CONSISTING OF THE AMMONIUM, SODIUM, LITHIUM, BARIUM, STRONTIUM AND POTASSIUM PEROXYDISULFATES AT A TEMPERATURE OF 50* TO 150*F. UNTIL THE COPPER IN AREAS FREE OF SAID RELIEF PATTERN HAS BEEN ETCHED AND REMOVING THE RESULTING ETCHED WORKPIECE FROM SAID AQUEOUS SOLUTION.
Claim 2
Dependent Claim
137 words
METHOD OF ETCHING COPPER BEARING A NOBLE METAL RESIST WITH AN AQUEOUS PEROXYDISULFATE SOLUTION WITHOUT PROVIDING EXCESSIVE UNDERCUTTING OF THE COPPER RELIEF PRODUCED THEREBY, COMPRISING PROVIDING A NOBEL METAL RESIST PATTERN ON THE SURFACE OF A METALLIC COPPER OBJECT, PROVIDING ON SAID RESIST PATTERN A COATING FROM THE GROUP CONSISTING OF TIN COATINGS AND COATINGS COMPOSED OF A TIN ALLOY FROM THE GROUP CONSISTING OF TIN-LEAD AND TIN-NICKEL ALLOYS CONTAINING AT LEAST 25% OF TIN, CONTACTING THE RESULTING WORKPIECE WITH AN AQUEOUS SOLUTION CONTAINING FROM 5% TO ITS SOLUBILITY LIMIT OF A PEROXYDISULFATE FROM THE GROUP CONSISTING OF THE AMMONIUM, SODIUM, LITHIUM, BARIUM, STRONTIUM AND POTASSIUM PEROXYDISULFATES AT A TEMPERATURE OF 50* TO 150*F. UNTIL THE COPPER IN AREAS FREE OF SAID RELIEF PATTERN HAS BEEN ETCHED AND REMOVING THE RESULTING ETCHED WORKPIECE FROM SAID AQUEOUS SOLUTION.
References Cited (Backward Citations)
US2731333A
Cited
US3137600A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-02-21 | 1969-08-23 | 1970-02-22 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-02-21 | 1973-08-23 | 1974-02-22 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-02-21 | 1977-08-23 | 1978-02-22 | $7700.00 | Window Closed / Lapsed |